Probably the biggest share of "common" users will only open a single document at a time. But there are others around that sometimes have more than one single document open and who don't want to get their screen cluttered up with Acrobat documents.

From the thread above there's a Hyperlink to the Acrobat blog, justifying why MDI has been removed from the Acrobat GUI.

I believe the reasons given in there are wrong:

Feature Parity with Macintosh was desired. As stated before, the Mac OS does not have this option. While I will be the first to admit that feature parity is not 100% between Windows and Macintosh, it is a goal that we aim for.

As written at the top of the blog, "MDI is not applicable on the Mac OS." So this is simply a system feature not available to Mac OS but to Windows. Parity in regard to system environment can never be achieved. Otherwise, Acrobat would have to strip keyboard support, because smartphones like the IPhone lack the presence of a keyboard.

Utilizing MDI is quite transparent to the software when being programmed properly. The client area to draw into won't be different. And the Mac OS will simply display like an MDI environment with just one document in it..

In version 8, we made SDI the default in the viewing mode. Making SDI default, but still providing MDI in version 8 was done to start the deprecation of MDI.

This is no reason at all. It's just a description of a decision you made..

Microsoft advised that to work as good as possible on Vista, applications should avoid MDI.

MDI is currently still available in any document centric Microsoft application. And it's available in any current document centric Adobe software - except for Acrobat.

WPF is commonly used as the successor of MDI, yet multiple-document GUIs are fully supported in Windows..

Acrobat and Adobe Reader’s new UI modes would not work with MDI. Form editing mode, portfolio mode, and portfolio preview mode all wanted a complete refresh of the UI. MDI mode always left a bit of the UI skin under the care of an MDI main frame, so there would have had been no way for those UI modes to re-skin that part of the UI if MDI mode was left in place.

Perfoming these modes in MDI, WPF or any other multi-document environment would just have been a matter of good program design. Nothing more.

And again, if Mac OS does not support MDI, it's still possible to abstract the display concept to address SDI/MDI differences transparently in the Acrobat application. Microsoft Office even demonstrates how this is done: In all the MS Office applications there is an option to switch between MDI/SDI ("Show in Task bar")..

A cost compelling reason was that MDI and SDI mode essentially became another view mode in which all work flows had to be tested. This increases the cost of testing the product and the cost of fixing bugs. Often a fix to a bug in one view mode would cause adverse reactions in the other view mode. The decision to support only one view mode on Windows was made to simplify this. Furthermore, more time spent in this area could mean less time spent developing and fixing bugs in other areas.

That's true, alright. - But automated testing tools also decrease the cost of testing. And as far as I know, testers do not develop software. That's the developers' task. So performing more testing in this area does not result into spending less time for developing. This is particularly true once the framework had been established to deal with MDI/SDI transparently.

I strongly suggest to return to MDI. The implementation classes should still be available from Acrobat 8. Perhaps they'd need a redo in order to support a better, transparent program design.

This debate has gone around many times, and overall the target customers for the Acrobat Family (enterprises with knowledge workers) much prefer a completely-uniform experience across the supported platforms (Windows and OS X*) as it reduces training costs.

The Acrobat Family code handing the UI is optimized for SDI, and in version X we rely heavily on changing 'modes' based on what's happening to the document - a window displaying a PDF Portfolio is totally different to one displaying a PDF form, with real estate reused between modes to support smaller displays such as netbooks. Acrobat X will fit on 1024x576, Photoshop wants at least 1024x768, ideally 1280x800.

With other applications (such as Photoshop) the UI panels and toolbars can be arranged how you want and are always relevant to every document, even if some of the panels are empty - that isn't the case with Acrobat where pretty much the only thing shared across all documents is the OS menu and window control buttons. The goal is to only display UI features pertinent to the current task, always in the same place. In an enterprise setting it's important that people can use applications with the minimum training and that they aren't confused by customizations made by whomever sat at that machine last. It was a complaint with Acrobat 9 and earlier, where you could change it beyond recognition.

*The mobile editions of Adobe Reader are entirely different - they have their own style of UI, they're developed by a separate team, and Acrobat doesn't exist on mobile.

And I understand that Acrobat (Reader) seems to predominantly target enterprise users running a heterogenous environment. Although I guess there shouldn't be too many of them, as the IT department would go nuts rolling out and supporting different OSs througout the company. The blue-chip enterprises I had been working for never rolled-out more than one OS for their users throughout the country.

Nonetheless, I guess actual user performance counters of Acrobat Reader should demonstrate that this tool is overwhelmingly used by users not getting a specific training for.

Moreover, Acrobat could be preset to display SDI after installation, providing an MDI option in the Preferences dialog. Just like you did with Acrobat 8.

Last but not least: UI settings could be easily set when a document in an MDI environment becomes active. Microsoft Visual Studio, for example, already changes its GUI depending on the currently active document. - It wouldn't even require much additional programming effort. Just run the same UI set-up code on MDI child window activation you currently run when opening a document.

One thing, for example, has become quite clumsy now: Comparing different versions of documents against each other.

Previously one could just open them from within the MRU list in Acrobat, set those MDI windows to maximized layout and press CTRL+TAB to compare each PDF document against each other while the Acrobat program window itself could stay next to another designer program's window.

Nowadays, when comparing different PDF documents against each other, the user must close all other application windows, or else they will permanently show up while rotating through the different Acrobat program windows.

Plus, each of the Acrobat windows must be maximized manually. Comparing 6+ different versions becomes heck now.

I don't care what you do with Acrobat Reader. Acrobat Professional should have MDI. Everyone complaining uses it for work and is paying, not downloading the free reader. My work computer was just upgraded to Windows 7 and my old Pro version of Acrobat is not compatible. I downloaded the X Pro trial and can not stand SDI, and can not believe there is no option for MDI. I have spent hours searching for a solution and am even trying non-Adobe programs that may do a better job (if Nitro would drag pages from one pdf to another, and had side by side view instead of just tabs I would be using it now). Having 10 multi-page documents open to compare and edit, then having a priority call or e-mail come in and having to minimize each one of them and then go back and reorganize them is a PITA. I want one window to click to put all Acrobat items in focus. If this is such a "feature" why don't you change Photoshop to work like this? It is horrible. Why don't you have Acrobat 8 Professional as a download? Right now, I would pay for that. I guess I am going to be searching e-bay for a Acrobat 8 Professional CD, then getting a purchase order so I can be reimbursed. Adobe, do you realize that I would much rather just have my company pay for the X version? How bad is dropping MDI that I would go to that much trouble. FYI, to vent on this subject was the only reason I joined.

KlausKi, you can use Ctrl+F6 for this specific purpose. AFAIK there is no way to port the same function to the-traditional-and-so-convenient-single-handedCtrl+Tab.

Use Ctrl+Shift+F6 to go back (useful when switching more than two, obviously... )

However I do agree with your initial post in all its points and I do miss the SDI as all the other kids, I also am able to understand the pragmatism of Adobe in this case (understand but disagree).

Adobe reminds me here a vegetable salesman, who decides not to wash the now-so-popular first class organic very tasty potatoes anymore, as it is too dirty job for him with no income effect, while the people appreciating the quality of his potatoes will come regardless of how dirty they will be. Though the salesman should be cautious with the next austerity applied. People might stop buying in his shop if the vegetables would be suddenly second class, not so tasty or worse, rotten.

KlausKi wrote:

One thing, for example, has become quite clumsy now: Comparing different versions of documents against each other.

Previously one could just open them from within the MRU list in Acrobat, set those MDI windows to maximized layout and press CTRL+TAB to compare each PDF document against each other while the Acrobat program window itself could stay next to another designer program's window.

Nowadays, when comparing different PDF documents against each other, the user must close all other application windows, or else they will permanently show up while rotating through the different Acrobat program windows.

Plus, each of the Acrobat windows must be maximized manually. Comparing 6+ different versions becomes heck now.

Thanks. My first statement was less meant as 'add this feature or else' and more 'I sure hope this feature is present when I get my hands on the product,' because I can't find a confirmation of this feature (or its continued absence) in information published in the store portion of the website. This could be my failure to find it, but I suppose since there has been no change since two versions ago, it wouldn't make sense to mention it there, so my guess is that it's not there. Searching the forums keeps bringing me back to these X and 9 threads.

Frankly, from a user persepective the "reasons" we've been given don't justify the choice. I get that putting MDI back would be hard and expensive, but it would also be correct. Acrobat Pro is in fact used in ways that are equivalent to other programs in the Suite. It is used in design and publishing environments that are more interested in task efficiency than homogeny of user experience. It's great that particular interests have demanded particular features from Acrobat, and that Acrobat has obeyed, but other users suffer from the result.

Actually, let me say something about homogeny of user experience. It seems like a fairly reasonable approach to this challenge is to come up with a UI that is intuitive based on knowledge users can be assumed to have from other UIs they can be assumed to be using. Acrobat's approach seems to be to come up with its own UI that is not only completely unlike the major OSes, but also unlike everything else Adobe does. Dividing Acrobat from Windows, Mac, etc. — sure, that's only fair. But why divorce it from the rest of its own sister products? The results have been strange.

I really didn't come here to rant about the UI, and obviously my rant can't even take into account whatever's happened to the UI in version XI. What we have in X is obviously designed for the benefit of organizations that lobbied Acrobat for specific needs and not for a public user base - but I've adapted, and so has everyone else, and now all I want is MDI. I will work with whatever menu/sidebar design Acrobat wants to invent. Suffering through the inability to corral windows the way every other program has for many years is just a little too much.

Acrobat was never a part of Creative Suite, it was merely included in the collections. The CS applications were developed by a different unit within Adobe to the 'enterprise' applications like Acrobat and LiveCycle. The creative business unit developed their own interface system (OWL) but it wasn't adopted by the other teams as it was specifically designed for one type of user, who worked on multi-screen hardware with highly customized desktops and took the time to really learn the software in depth.

The same is true of the consumer programs (Lightroom, etc.) - their target users have different hardware and skill levels, and their UIs reflects that. A Lightroom user doesn't need workspaces, and by discounting that the UI is free to implement something that makes more sense to photographers. In the OWL UI, you tend to have multiple information streams presented to the user in different panels, rather like an aircraft cockpit. The user is doing something with one tool, but can pull information from other panels as required. If they're editing text they need to see the swatches and styles panels. In Acrobat however, the workflow is single-task-based. You pick a tool, do something with it, then pick another tool. While you're editing a watermark there's no reason you would want to see the ink manager dialog or the XMP metadata.

Of course I see the logic in having a tabbed interface, but for everyone it pleases there'll be someone who begrudges the space taken up by the tabs on their netbook screen, or the fact they can't drag one file onto a second monitor. Adobe would have to keep both interface options so you could switch between them, and that pretty much doubles the workload on every release.

I'm not saying that going forward there's no chance of a tabbed interface ever appearing in the Acrobat Family, but with respect the target users tend to get lost when the UI reinvents itself. Acrobat is just a tool like the photocopier for most people, they aren't going to spend weeks learning it as they would with Photoshop. Open>Redact>Save>Email, all day every day. Adobe's target customers (big enterprises) see any change, even one that "improves" the UI, as a nightmare of retraining and reduced productivity.

BendersonMath wrote:

Actually, let me say something about homogeny of user experience. It seems like a fairly reasonable approach to this challenge is to come up with a UI that is intuitive based on knowledge users can be assumed to have from other UIs they can be assumed to be using. Acrobat's approach seems to be to come up with its own UI that is not only completely unlike the major OSes, but also unlike everything else Adobe does. Dividing Acrobat from Windows, Mac, etc. — sure, that's only fair. But why divorce it from the rest of its own sister products? The results have been strange.

I am a college professor and a professional firm. I failed to realize that Acrobat had removed the MDI feature.

In the past, I have recommended to students, clients and my staff to set Acrobat as their 'default printer'. I keep one monitor with Acrobat and constantly print to it throughout the day.

After upgrading the Acrobat XI, a new window opens everytime I print - usually on top of my current work and never in the same place.

I just spoke to Acrobat support. They advised me to find clients with previous Acrobat versions and share these among computers. I was told this would be acceptable to Adobe until this problem is fixed. (we'll see what happens)

I am notifying my clients through my newsletter and all students to avoid Acorbat X & XI. DO NOT UPGRADE.

I have stopped all ongoing upgrades and am returning all new Acrobat purchases and I will be reinstalling Acorbat 9 on all computers.

Regarding the statement that this is necessary to achieve 'parity with Mac', I probably missed something. But my reply is: IF I WANTED A MAC i WOULD HAVE PURCHASED A MAC - BUT NEVER WITHOUT MDI.

For those of you who are doing what I am (reinstalling Acrobat 9), there are pdf printers out there that work well with Windows 7. I used Acrobat 9 with these printers for the last year. There was no difference and MDI worked like it is supposed to. Hope this helps.

I'm really glad I found this thread. I was looking around to see if X, or XI had gotten the MDI back. In short -- no. Adobe was supposedly 'working on making it available' back in 2008. Yeah. Right.

Adobe has given the finger to MDI, as attested to by their comments and closing off the 2008 discussion after 9 came out.

I am still running 8 and would like to update -- but not w/out MDI. If I can't get MDI from Adobe, I won't update Acrobat at all, I'll switch to another program.

I have to agree with Btsuperman and everyone else griping about this absurdity. If I wanted a Mac, I;d have a Mac. If my company wanted Macs, we'd run Macs. We run over 200 PCs and I run 6 at my res. They work -- as in real work. We also run iOS on phones and pads. They are good for what they are for -- but not for substantial work, not for us.

Adobe has proven one thing beyond any doubt, they have no intention of supporting MDI in Acrobat. Period.

That leaves all of us with one one thing to do: get over it and move along.

For some that will mean giving Adobe the same finger they've given us. For others... I don't have a clue. It is simply not possible to be as productive in an SDI environment working numerous applications and documents at the same time as it is in an MDI environment.